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Consider the following statements regarding the germination of pollen grain and choose the correct answer:
1. The content of the pollen is a true male gametophyte
2. The pollen tube comes out due to the protrusion of the exine through the germ pore
3. When the pollen grain has germinated, the pollen tube penetrates the stigma through the stigmatic papillae
4. Some stigmas have a continuous cuticle in which pollen tubes penetrate by enzyme action
Consider the following statements and choose the correct answer:
1. In angiosperms the pollination consists of transference of the pollen grains from the anther to the stigma either by self-pollination or by cross-pollination
2. Pollen grain is shed from the pollen sac in the two-celled stage
3. The exine of each microspore grows out into a tube, called the pollen tube
4. The growth of pollen tube is stimulated by sugary substances secreted by the stigma
Consider the following statements regarding Xenia and choose the correct answer:
1. If a white variety (yy) is pollinated with pollen from a yellow variety (YY), one of the male gametes (Y) will unite with the egg (y) to produce a hybrid embryo (Yy) which will act as a heterozygote for yellow endosperm in the next generation
2. The second male gamete (Y) will unite with the two polar nuclei (y, y) and produces the primary endosperm nucleus (Yyy) which is triploid
3. If a yellow endosperm variety (YY) is crossed with pollen from a white grained variety, the grains produced are white like the pollen parent
Consider the following statements and choose the correct answer:
1. Intense or strong light retards the growth of shoot
2. Shade plants are shorter and stockier than sun plants
3. Shade plants have dense covering of hairs while sun plants are less hairy
4. The stems of shade plants are taIler and more branched than that of sun plants
S1:Palaeobotany is the study of fossil plants preserved in rocks dating back in millions of years.
P :Records of the history of the world are contained in fossils.
Q :Through the ages, plants have evolved from simple to more complex forms.
R :First there were water plants then land plants appeared during the Paleozoic era.
S :But since the fossil remains appear locked in rock layers, they are closely related to the geologist area of investigation.
S6:The fossil plants indicate the age of the rock, and also point to facts regarding climate, temperature and topography.

The Proper sequence should be:
How many pollen mother cells will form 1000 pollen grains
A compound dissolves in water at a rate proportional to the product of the amount of undissolved solid and the difference between the concentration in a saturated solution and the actual solution; i.e., Csat – C(t). A saturated solution of this compound contains 40 g per 100 g of water. In a test run starting with 20 kg of undissolved compound in 100 kg of water, it was found that 5 kg dissolved in 3 hr. if the test continues, how many kg of compound will remain undissolved after 7 hr? Assume that the system is isothermal.
Consider the following statements and choose the correct answer:
1. The C4 plants can absorb CO2 even from a much low CO2 concentration when the C3 plants fail to avail it
2. The C4 plants require less energy to fix CO2 as compared to C3 plants
3. C4 plants are better adapted to tropical and desert areas where sunlight is more intense and the growing season is longer
4. Maize is a C4 plant
Plants have been used as healers and health rejuvenators since times immemorial. More than half the drugs under clinical use owe their origin to plants. The Glossary of Indian Medicinal Plants lists 3000 plants. Which part of the plants is used most for medicinal properties ? 
How do the pollen grains break open from the pollen sacs?